If your specifically referring to ETTs, both are subglottic ET tubes. The EVAC catheter itself is incorporated into an EVAC ETT that allows for suctioning secretions etc above the ETT cuff. There should be an external catheter line attached or incorporated into the EVAC ETT that allows you to hook it up to suction. Keep these suction levels at around 20-30 mmHg if continually aspirating secretions. Please check my video on the different types of ETTs for further clarification.
